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101.
Turek Z Cerny V Parizkova R Samek J Oberreiter M 《Journal of Zhejiang University. Science. B》2011,12(10):867-874
Objective
Hemodilution changes the physical properties of blood by reducing its hematocrit and blood viscosity. We tested whether prolonged hypervolemic hemodilution (HHD) impairs functional capillary density (FCD) of ileal mucosa in healthy mechanically-ventilated pigs and if there is any correlation between changes in FCD of ileal and sublingual mucosas during HHD. 相似文献102.
Vladimir N. KHMELEV Andrey V. SHALUNOV Roman V. BARSUKOV Denis S. ABRAMENKO Andrey N. LEBEDEV 《浙江大学学报(A卷英文版)》2011,12(4):247-254
The aim of this investigation was to define the effectiveness of non-contact drying using ultrasonic vibrations. Disk radiators
were used for carrying out experiments, and a special drying chamber was designed to provide resonant amplification of ultrasonic
vibrations (from 130 to 150 dB). Drying of ginseng and other vegetables demonstrated that the application of ultrasonic vibrations
reduced power inputs by 20% in comparison with convective drying. It also led to a decrease of 6% in final moisture content,
if the duration of drying was constant. The level of intensification of ultrasonic drying was high (up to 50 g for 1 kg of
drying material), which helped to lower the temperature of the drying agent and improve the quality of the dried products. 相似文献
103.
Microinjection with ultra-fine glass capillaries is widely used to introduce cryoprotective agents and other foreign molecules into animal cells, oocytes, and embryos. The fragility of glass capillaries makes difficult the microinjection of fish eggs and embryos, which are usually protected by a hard outer shell, called the chorion. In this study, we introduce a new electromechanical approach, based on the electropiercing of fish eggs with a stationary needle electrode. The electropiercing setup consists of two asymmetric electrodes, including a μm-scaled nickel needle placed opposite to a mm-scaled planar counter-electrode. A fish egg is immersed in low-conductivity solution and positioned between the electrodes. Upon application of a short electric pulse of sufficient field strength, the chorion is electroporated and the egg is attracted to the needle electrode by positive dielectrophoresis. As a result, the hard chorion and the subjacent yolk membrane are impaled by the sharp electrode tip, thus providing direct access to the egg yolk plasma. Our experiments on early-stage medaka fish embryos showed the applicability of electro-microinjection to fish eggs measuring about 1 mm in diameter. We optimized the electropiercing of medaka eggs with respect to the field strength, pulse duration, and conductivity of bathing medium. We microscopically examined the injection of dye solution into egg yolk and the impact of electropiercing on embryos'' viability and development. We also analyzed the mechanisms of electropiercing in comparison with the conventional mechanical microinjection. The new electropiercing method has a high potential for automation, e.g., via integration into microfluidic devices, which would allow a large-scale microinjection of fish eggs for a variety of applications in basic research and aquaculture. 相似文献
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Like other cultural industries, the theatrical film industry is subject to the ‘blockbuster effect’, where popular products often dominate their competition by orders of magnitude over relatively short-run time horizons. This paper investigates this particular feature of the industry and the implication for overall market size. Using simple regression analysis, a positive relationship between (product-level) market concentration and market size is established using weekly box office revenue data from the US motion picture industry. This empirical evidence supports a simple theoretical model of heterogeneous consumers who selectively participate in the market. 相似文献
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